EN
The paper presents a technique for measuring membrane displacements with one motionless camera. The method relies on measuring the distance to an object based on one image obtained from a motionless camera with a fixed-focus lens. It is proven that the used technique allows monitoring the frequency and amplitude of vibration. The tests were performed for the oscillation frequency in the range from 0.5 Hz to 6 Hz and deviations from the neutral position in the range of ± 3 mm.